DE 10 2007 037 229 A1 describes an opening cylinder for an open-end spinning device that has a core piece over which the opening cylinder is fastened to a drive shaft. Moreover, the opening cylinder has a tooth-set carrier fastened to the core piece by a clip connection in the axial direction. Furthermore, the opening cylinder has a device for the form-fitting connection of core piece and tooth-set carrier in the circumferential direction that comprises a projecting part and recess acting in conjunction with it. At the same time, the projecting part forms a snap-on shoulder of the projecting part. The disadvantage of this design is that, owing to the axial clip fastening, the connection has only a low axial retention force. Thus, during operation, the oscillations and vibrations can create a play between the tooth-set carrier and the core piece so that fibers can get stuck in the connecting area of these two components. They start accumulating and create a fiber ball that detaches after a certain amount of time, thus causing impurities and/or uneven spots in the yarn.